Two-stage single diaphragm valve



March 7, 1961 1'. J. SULLIVAN 2,973,935

TWO-STAGE SINGLE DIAPHRAGM VALVE Filed Oct. 21, 1957 4 Sheets-Sheet 1 IN VENTOR ATTORNEYS March 7, 1961 T. J. SULLIVAN 2,973,935

TWO-STAGE SINGLE DIAPHRAGM VALVE Filed Oct. 21, 1957 4 Sheets-Sheet 2 ATTORNEYS March 7, 1961 T. J. SULLIVAN 2,973,935

TWO-STAGE SINGLE DIAPHRAGM VALVE Filed Oct. 21, 1957 v4 Sheets-Sheet 3 BY i64 y AfTO ZIZ S March 7, 1961 Filed Oct. 21, 1957 T. J. SULLIVAN TWO-STAGE SINGLE DIAPHRAGM VALVE 4 Sheets-Sheet 4 A L l I 69 65? IN VENTOR ATTORNEYS TWO-STAGE SINGLE DIAPHRAGM VALVE Timothy J. Sullivan, Butte, Mont., assignor to Sullivan Valve and Engineering Company, Butte, Mont, a corporation of Montana Filed Oct. 21, 1957, Ser. No. 691,362

Claims. (Cl. 251-30) This invention relates generally to a two-stage valve for regulating the supply of gas to the boilers of power plants, heating plants and the like, and more particularly to a two-stage control valve provided with only one single diaphragm pressure-responsive operating member.

It has been well known in the past, as illustrated by my issued Patent #2,333,2l2 and my application Ser. No. 583,893 which has now issued as US. Patent No. 2,825,510, to provide two-stage two-diaphragm valves which will open to a first low-fire position where a limited amount of fuel is supplied to the burner to heat the furnace flue sufliciently to create a draft therethrough, and which will then open to a fully open high-fire position to permit a maximum supply of fuel to the burner.

The primary object of the instant invention is to provide a two-stage control valve for fuel burners which has only one single-diaphragm operating member.

Another object of my invention is to provide a twostage single-diaphragm valve which is controlled by the operation of a three-way solenoid operating valve and a two-way solenoid positioning valve.

A more specific object of my invention is to provide a two-stage single-diaphragm valve of the type described having a valve stem secured to the diaphragm and adapted to simultaneously operate micro-switches associated with the solenoids of the operating valve and the positioning valve when the diaphragm attains a low-fire position.

Still another object of my invention is to provide a two-stage single diaphragm valve of the type described in which the micro-switch of the operating valve'will be actuated when the diaphragm valve is open above the low-fire point and in which the micro-switch of the positioning valve will be actuated only when the diaphragm operator is at the low-fire position. Q A further object of my invention is to provide a twostage single-diaphragm valve having means for readily adjusting the degree of valve opening at-the lowand high-fire positions.

Other objects and advantages of my invention will be' cornemore apparent when considered in'view of the following specification and drawings, in which:

Fig. v1 is a partially sectioned side elevational view of my two-stage single diaphragm valve; I '7 Fig. 2 is a partially sectioned end elevational view of I the valve; 1

Fig. 3 is a plan view of my valve;

Fig. 4 is asemi-schematic diagram of 'the system embodying the invention. a

Referring now more particularly to Figs; 1 and 2, the

valve body 1'is of the full-flow type having an inlet chamber 2 and an outlet chamber3 divided by a trans- I verse Wall 4 having a valve seat 5 mounted .thereintp' Bolted to the upper portion ofthe valve. body 1 by boltsfi and 7 is the bonnet 8 which has: a portion8a which extends into the valveibody. Pivotally connected to thejbonnet portion 8a upon fixed pivot 9 is the ,valve 2 V V 'arm 10 upon. which isfsecure'd the valve member, 11 "-;5;i Associated with operating rnember 341 and'wmicr States Patent end to bolt 17 of the diaphragm plate assembly and at the other end to valve arm 10 is the connecting link 21. The arrangement is such that upon upward movement of diaphragm 16 and the diaphragm plate assembly carried thereby within the pressure motor housing 13, link 21 will be moved upwardly to pivotally lift arm 10' and valve member 11 secured thereto from the valve seat 5.

Rigidly secured within the opening of the upper portion of the pressure motor housing 13 is sleeve 22 having a bore 22a in the lower portion thereof. Slidably movable inbore 22a is stem 23 which is fixedly secured at its lower extremity to the bolt 17 of the diaphragm plate assembly. Rotatably supported in the upper portion of sleeve 22 is cylindrical member 24 having a nected at one end by fixed pivot 28 to the stationary arm 28' secured to the pressure motor housing and carries at its other end a weight member 29. Chain 30 connected to lever 27 adjacent the weight member 'may'be utilized, as is customary in the art, for the mechanical control of auxiliary apparatus, such as the secondary air doors of an associated. gas-fired furnace, as will be explained in greater detail below.

Threadably connected to the lower portion 24b of cylindrical member 24 is the switch operator guide sleeve 31. The position of sleeve 31 within sleeve 22 may be adjusted vertically by rotationalmovement of cylindrical wall of the switch operator guide sleeve 31 are the micro: switch operating members 34 and -35.

members extend through apertures 22avin sleeve na ls terminate at their outer ends in vertical plates 36937 respectively. Spring means, not showmtend to urgefthe operating members 34, 35 radially inwardly'toward'the" 3 operating rod'26. Associated with operating member 34 and adapted to be operated thereby is micro-switch) switch 60 will be opened and the contacts'of micro switch 61' will be simultaneously closed when theroun dedf upper extremity of stem 23'contacts the-operating mem- ,1 ,bers 34 and 35 to-urge the same radially outwardly'upon I upward movement of diaphragm 16 to'the low-fire position as willbe explained in greater detail below. The side of stem. 23 adjacent operating member 35- has-jal vertical recessed portion 23b therein so arr'anged lth'at uponfurther upward motion of stern 23,loperating me ber. 35 will be allowed to moveto thelefft in Fig. 2 the biasing force of the spring; means andftlie contacts of mic'ro-switch '61" will again be, opened.

These operating V switch 60 is a three-way solenoid operating valve 38 and associated with operating member 35 and micro-switch 61 is a two-way solenoid positioning valve 39. As shown in Fig. 1, the valve body 40 of the three-way solenoid valve 38 has a vertical bore therein and an inlet opening 41 in the wall thereof in communication with the pressure motor lower chamber 15 by means of the conduit 42. Threadably connected within the bore of valve body 40 is a transverse partition 43 having a bore 43a through which the solenoid plunger 44 extends. The plunger 44 has an enlarged head 45 having a tapered lower portion adapted to seat upon the tapered seat of passage 46 to close the same when the plunger is in the solenoid-de-energized lower position of Fig. 1. Gas under pressure may then be conducted from the pressure motor lower chamber 15, through conduit 42 and inlet opening 41, through the bore 43a about the plunger 44, out the outlet opening 47, and through the conduit 49 to the solenoid positioning valve 39. When the solenoid 38a of valve 38 is energized, plunger 44 is moved upwardly by electro-magnetic attraction to cause valve member 50 on the plunger to close the passage through bore 43a and to allow communication between outlet opening 47 and the atmospheric vent opening 51 through passage 46.

Referring now to Fig. 2, when the plunger 44 is in the de-energized lower position shown in Fig. 1, gas will be conducted from conduit 42, through the bore passage 43a of the three-way solenoid body 40, and through the conduit 49 to the inlet 52 of the valve body 53 of the simple solenoid valve 39. Valve body 53 has a vertical bore with a transverse partition 54 therein porvided with a bore 54a therein. Extending through the bore 54a is thesolenoid plunger 55. When the solenoid plunger 55 is in the de-energized lower position of Fig. 2, communication through the valve body 53 is provided between conduit 49 and conduit 56 connected to the upper diaphragm chamber 14 (see Fig. 1) through opening 52, through the bore 54a about the plunger 55, and through the outlet opening 57.

Referring now to Figs. 3 and 4, the electrical connections of the valve and its associated electrical equipment will be described in order that the operation of the valve may be subsequently presented.

As shown somewhat schematically in Fig. 4, gas under pressure is fed through conduit 62 and valve body 1 to the furnace chamber of the steam boiler 63. The opening of the secondary air doors 64 of the boiler may be adjusted by chain 30 and lever 27 in accordance with the position of operating rod 26, diaphragm 16, and valve arm 10. Stack switch 65 is provided in the flue of the furnace and has normally closed contacts which will be opened when the flue temperature exceeds a desired predetermined value. Low-fire pressure responsive switch 66 and high-fire pressure responsive switch 67 are connected in boiler pipe 68 and are operated in accordance with the steam pressure therein. As shown in Fig. 3, the stack switch 65 and the low-fire limit switch 66 are single pole switches having normally closed switch contacts, and the high-fire limit switch 67 is a single-pole double-throw switch.

The operation of my two-stage single diaphragm valve may now be readily described. a

When the solenoid valves are in their de-energized state with the plungers in the lower positions in Figs. 1 and 2, gas under pressure will be conducted from the valve inlet chamber 2,'through the opening 8b in the bonnet 8 and into the lower chamber 15 of the pressure motor 13. The gas will then be conducted through conduit 42, bore 43a in the three-way solenoid valve bodyj49, through conduit 49 and bore 54:: in the two-way solenoid valve body 53, and through the conduit 56 to the pressure motor upper chamber-14. Thusuthe pressurefis equalized onboth sides of the diaphragm 16 and the diaphragm willremain stationary and valve arm will maintain valve member 11 in seated engagement with valve seat 5. It should be mentioned that the mass of weight member 29 and lever 27 upon operating rod 26 and stem 23 will assist in causing diaphragm 16 to remain in its lower position in Fig. 1 and to retain valve member 11 in engagement with the valve seat 5 by means of connecting link 21.

When the solenoid 38a is energized upon actuation of switch S calling for heat, plunger 44 is raised by magnetic attraction to seat valve member 50 upon the transverse member 43 to close passage 43a. The current path for the energization of solenoid 38a will be from the positive source, through low-fire limit switch 66, through closed contacts of micro-switch 60, and through the solenoid 38a to the negative source. The upper chamber 14 of the pressure motor 13 will then be vented to the atmosphere through conduit 56, bore 54a in valve body 53, conduit 49, passage 46 in valve body 40, and vent outlet 51. Since the pressure in lower chamber 15 will be greater than the pressure in upper chamber 14 in the pressure motor housing, diaphragm 16 will begin to move upwardly to pivotally raise arm 10 and to lift valve member 11 from its associated seat 5. Stem 23 secured to the diaphragm plate assembly will slide axially upwardly within the bore of sleeve 22 and within the bore of the switch contact guide sleeve 31 until the upper rounded extremity of stem 23 engages the contact operating members 34, 35 and urges the same radially outwardly to close the contacts of microswitch 61 and to open the contacts of micro-switch 60. The diaphragm 16 will then be in its low-fire position and valve arm 10 will be partially raised from the seat 5 to permit partial passage of gas through the valve body 1. Solenoid valve 38 will de-energized and plunger 44 will drop to its lower position to close the vent outlet passage 46. Simultaneously, solenoid 39a will be energized to attract plunger 55 upwardly to trap the fluid in upper chamber 14 to lock diaphragm 16 and valve arm 10 in their low-fire positions.

As long as the stack switch remains closed, the valve cannot be opened further and valve arm 10 will allow partial passage of fluid through the valve body 1. After the chimney has been heated sufficiently to create a desired draft therethrough, stack switch 65 will be opened and the high-fire limit switch will be actuated so that the solenoid 38a will be energized by the electrical path from the positive source through the low-fire limit switch, through the high-fire limit switch, and through the solenoid 38a to the negative pole. Plunger 44 will thus be attracted to open the vent passage 46, and since switches 65 and 67 are open and the current source to solenoid 39a is broken, plunger 55 will drop and upper chamber 14 will be vented to the atmosphere through conduits 56 and 49 so that the diaphragm 16 will be raised to its fully open position by the gas pressure in inlet chamber 2. Operating member 35 will then be moved to the left in Fig. 2 by suitable spring means so that its rounded extremity will be positioned within recess 23b.

When the high-fire limit switch 67 switches to the oifposition when the heat demand is satisfied, the current supply to solenoid 38a is broken and gas will flow from the lower chamber 15 to the upper chamber 14through conduits 42, 49 and 56 to equalize the pressure on either side of diaphragm 16 so that said diaphragm will move downwardly due to the mass, of weight member 29 and lever 27. However when the valve stem 23 drops, op-

crating member 35 will ride along the wall of recess ber 35 so that passage 54a will be closed to trap the fluid in the upper chamber 14 and cause diaphragm 16 and valve arm10 to be in their low-fire positions. Should and the fluid pressure in upper and lower chambers 14' and 15 would be equalized and diaphragm 16 would move downwardly to seat valve member 11 upon the seat 5.

Thus it is apparent that according to my invention a simple two-stage valve is provided which requires only one diaphragm pressure motor, one three-way solenoid valve, and one two-way solenoid valve.

The adjustment of highand low-fire positions of the diaphragm 16 (and accordingly the degree of opening of the valve member 11) may readily be accomplished as follows. To adjust the low-fire position, setscrew 69 is loosened and the cylindrical member 24 is rotated with respect to sleeve 22. Due to the screw-thread connections, switch contact guide sleeve 31 will be moved vertically with respect to sleeve 22 so that the contact members 34 and 35 carried thereby will also be moved vertioally with respect to sleeve 22 and the pressure motor housing 13. Vertical plates 36, 37 will also be moved vertically with respect to microsw-itches 60, 61, respectively, but will still be in contact with the same. The degree of upward movement of diaphragm 16 and valve arm 10 for high-fire may be controlled by the vertical setting of nut 25 with respect to cylindrical member 24. Projection 26a of the operating rod 26 will contact the lower surface of nut 25 to limit the upward extent of travel of rod 26, stem 23, diaphragm 16, and valve arm 10. a

It is to be noted that the lower extremity of operating rod 26 is only loosely guided in the bore 23a in the upper end of stem 23. The advantage of this loose connection is that the blocking or manual lifting of lever 27 will not resultin a lifting of diaphragm 16 and a corresponding lifting of valve arm 10, and hence the automatic means for opening the valve are isolated within the apparatus housing.

While in accordance with the patent statutes, 1 have illustrated and described the best embodiment of my invention now known to me, it will be apparent to those skilled in the art that certain changes or modifications might be made in the apparatus described without deviating from the scope of my invention as set forth in the appended claims: 7

I claim:

1. Two-stage valve control means adapted to be connected in series in the gas supply main of a gas burner comprising a valve body having an inlet chamber and an outlet chamber divided by a transverse wall having an opening with a valve seat mounted therein; a valve member in said inlet chamber adapted to be seated on said valve seat to close the passage between said inlet and outlet chambers; a pressure motor having a housing divided into an upper chamber and a lower chamber by a flexible diaphragm mounted therein, said lower chamber being in communication with said valve body inlet chamber; means connecting said diaphragm to said valve member so that when said diaphragm has a first lowermost position in said housing said valve member will be seated upon said valve seat, so that when said diaphragm has a second intermediate position in said housing said valve member will be partially opened to a low-fire position relative to said seat, and so'that when said diaphragm has a third uppermost position in said housing said valve member will be fully opened to a full fire position relative to said seat; and means controlling the position of said diaphragm within its housing comprising a conduit connecting said lower chamber with said upper chamber, a three-way solenoid valve having an inlet and a first outlet connected in series in said conduit, a two-way solenoid valve having an inlet-and an outlet connected in series in said conduit intermediate said three? way solenoid valve and said upper chamber, said three" way solenoid valve having a second outlet vented to the atmoshpere, said three-way and two-way solenoid valves" each having solenoid-operated plunger means so arranged that when both said solenoid valves are in their de-energized states the vsecond outlet of said three-way solenoid 1 valve will be closed, the two-way solenoid valve will be open, and the pressure. in theupper and lower diaphragm chambers will be equalized through said conduit, means energizing said three-way solenoid to actuate the plunger thereof to close'said three-way solenoid valve inlet and to connect s'aid three-way solenoid valve outlets sothat the pressure in said upper chamber is vented through. said two-way solenoid valve and through the outlets let and the outlet of said two-way valve and thus tnap gas in said upper chamber to prevent further upward movement of the diaphragm and further opening of the valve member from said seat, and means for subsequently de-energizing said two-way solenoid valve when said diaphragm is in said second position to again vent said pressure motor upper chamber to atmosphere to cause said diaphragm to be further moved upwardly to its third uppermost position in said housing.

2. Gas burner control means as defined in claim 1 and further including voltage source means supplying electrical energy to the solenoids of said two-way and three-way solenoid valves, and further wherein said means for energizing said two-way solenoid valve comprises a stem slidably mounted in said housing and connected to said diaphragm'for movement thereby, a first electric switch having normally open switch contacts connected in series with the voltage source means supplying electrical energy to said two-way solenoid valve, and Ya first switch operating member connected to said housing adjacent said stem, said switch operating member being operable by said stem when the diaphragm is in its second intermediate position to close said switch 6011-. tacts and thus energize said two-way solenoid valve.

3. Apparatus as defined in claim 2 and further including means for de-energizing said three-way solenoid valve when said diaphragm is in the second intermediate position in said housing comprising a second electric switch having normally closed contacts connected in series with said voltage source means supplying electrical;

energy to said three-way solenoid valve, and a second switch operating member secured to said housing ad-i jacent said stem for actuation thereby simultaneously with the actuation of the switch operating member or said two-way solenoid valve to break the electrical con-i tacts of said second switch and thus de-energize said g I three-way solenoid valve, and means for subsequentlyk re-energizing said three-way solenoid valve upon high- 3 fire demand when said diaphgram is in its second intermediate position. I

4. Apparatus as defined in claim 3 wherein said means for subsequently re-energizing said three-way solenoid 7 second stationary contact when high-fire operation is demanded and in engagement with said first stationary contact when high-fire operation is not demanded; and circuit means connecting said two-way and three-way solenoid valves in parallel with said voltage source, one branch of said circuit means comprising said stack switch, said first switch and the solenoid of said two-way valve all connected in series, the other branch of said circuit means comprising said second switch connected in series with the solenoid of said three-way valve, the second contact of said high-fire limit switch being connected to the other branch of said circuit means intermediate said second switch and said solenoid of said three-way valve to energize the same upon high-fire demand, the first stationary contact and the movable contact of said high-fire limit switch being connected in parallel across said stack switch, said stack switch means being opened when the resultant burner heat reaches a desired amount as a result of low-fire operation of the apparatus to deenergize said two-way valve when the movable contact of said high-fire limit switch is in contact with said second stationary contact and thus vent the upper diaphragm chamber to cause movement of the diaphragm to the third uppermost position.

5. Apparatus as defined in claim 2 wherein said first switch operating member is biased into engagement with said stem and further wherein said stem has a recess therein to receive said first operating member to temporarily break the electrical contacts of said first switch when said diaphragm moves upwardly from its second References Cited in the file of this patent UNITED STATES PATENTS Berkholder July 19, 1949 Dalton Nov. 12, 1957 

